Season the shrimp with salt and pepper. Heat the oil in a large skillet or sauté pan over medium heat. Add the shrimp and cook for 1 to 2 minutes, until just firm. Remove to a plate. Add the pepper flakes, onion, garlic, and oregano to the pan; cook until the onions are soft. Add the tomatoes and wine and simmer for 10 to 15 minutes. Meanwhile, cook the spaghetti according to the package instructions. Drain and return to the pot. Season the sauce with salt and pepper. Fold the cooked shrimp into the sauce. Pour the pasta and toss. Serve garnished with the parsley.